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<p>A general approach to numerically simulating wear in rollingand sliding contacts is presented in this thesis. A simulationscheme is developed that calculates the wear at a detailedlevel. The removal of material follows Archard’s wear law,which states that the reduction of volume is linearlyproportional to the sliding distance, the normal load and thewear coefficient. The target application is the wheel-railcontact.</p><p>Careful attention is paid to stress properties in the normaldirection of the contact. A Winkler method is used to calculatethe normal pressure. The model is calibrated either withresults from Finite Element simulations (which can include aplastic material model) or a linear-elastic contact model. Thetangential tractions and the sliding distances are calculatedusing a method that incorporates the effect of rigid bodymotion and tangential deformations in the contact zone.Kalker’s Fastsim code is used to validate the tangentialcalculation method. Results of three different sorts ofexperiments (full-scale, pin-on-disc and disc-on-disc) wereused to establish the wear and friction coefficients underdifferent operating conditions.</p><p>The experimental results show that the sliding velocity andcontact pressure in the contact situation strongly influencethe wear coefficient. For the disc-on-disc simulation, therewas good agreement between experimental results and thesimulation in terms of wear and rolling friction underdifferent operating conditions. Good agreement was alsoobtained in regard to form change of the rollers. In thefull-scale simulations, a two-point contact was analysed wherethe differences between the contacts on rail-head to wheeltread and rail edge to wheel flange can be attributed primarilyto the relative velocity differences in regard to bothmagnitude and direction. Good qualitative agreement was foundbetween the simulated wear rate and the full-scale test resultsat different contact conditions.</p><p><b>Keywords:</b>railway rail, disc-on-disc, pin-on-disc,Archard, wear simulation, Winkler, rolling, sliding</p>

Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Fotis Papoulias, Anthony J. Healey. Includes bibliographical references (p. 83). Also available online.

Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Leamy, Michael; Committee Member: Costello, Mark; Committee Member: Ferri, Aldo. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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No description available.

This thesis was written for a Swedish valve manufacturer to find out in what temperature regimes it was possible to replace electroplated hard chromium with autocatalytic electroless nickel-phosphorus. In this work the dry sliding wear properties of electroplated hard chromium and autocatalytic electroless nickel-phosphorus(10% P) were compared. All tests and investigations were done by using available equipment at Karlstads University. The tests were made to find out how the wear of these coatings behaved at different temperatures, how different substrates influence the wear of these coatings and how the roughness of the substrate surface influence the wear properties of these coatings. The method used for the wear tests was block-on-ring with a counterformal contact mode. The tests were executed in room temperature, 300C and 400C; with a normal load of 100N, sliding speed was 150rpm and duration of the tests were 15 minutes. All tests were done in an argon gas atmosphere. The coatings was deposited onto the cylinders with a thickness of 30µm. The different substrates used were an austenitic stainless steel(1.4404) and an austenitic-ferritic(duplex) stainless steel(1.4460). Half of the austenitic cylinders had a machined surface and all the others(including duplex cylinders) were machined and grinded to achieve a smoother surface. The blocks used as countersurface were made out of austenitic-ferritic(duplex) stainless steel(1.4460). Equipment used to investigate the wear tracks were stereo microscopy, profilometer, microhardness tester and scanning electron microscopy(SEM). The coatings were investigated in matter such as wear depth, wear mode, wear mechanism, chemical composition, topography, morphology, cross-section and hardness. The results of this work showed that the nickel coating wear tracks maximal depth were less deep than those of hard chrome, at room temperature. At elevated temperatures the performance varies. The coatings deposited onto cylinders made out of duplex stainless steel performed better than those deposited onto austenitic cylinders. The nickel coating performed better deposited onto the substrates with smooth surface and the chrome coating performed better deposited onto the substrates with rough surface

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 131-136).

Thesis (Ph. D.)--Carleton University, 2005. / Includes bibliographical references (p. 159-166). Also available in electronic format on the Internet.

Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2007. / Jeffrey Streator, Committee Member ; Richard Neu, Committee Member ; Itzhak Green, Committee Chair.